Why does gravity affect time?

In summary, Einstein's idea of space-time as a 2 dimensional grid with "planets" sitting on it stretching it out is not an accurate representation. The effects of gravity on time are not just semantics, but a fundamental aspect of relativity. Gravity affects both space and time, and this is necessary to explain phenomena such as gravitational time dilation and the motion of objects in a gravitational field. Visualizations and animations can help to better understand the concept of space-time and its relationship to gravity.
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I understand that Einstein had the idea of space as a 2 dimensional grid with "planets" sitting of the grid, stretching it out, but I don't get why this affects time.
 
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adimantium said:
Why does gravity affect time?

Gravity doesn't affect "time", it affects "spacetime". This is not just semantics. There are plenty of place on the internet to read about this.
 
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adimantium said:
I understand that Einstein had the idea of space as a 2 dimensional grid with "planets" sitting of the grid, stretching it out, but I don't get why this affects time.

Think about it: If gravity was just distortion of space, how would it ever affect objects that are initially at rest in space? The distortion of spatial distances can only affect objects which already move through space. But why would an apple start falling from rest. Obviously the time dimension must be distorted too, to affect the apple that initially advances only through time. See animation below:

https://www.youtube.com/watch?v=DdC0QN6f3G4

See also this pictures that visualize the different effects of gravity:

http://www.physics.ucla.edu/demoweb..._and_general_relativity/curved_spacetime.html
 
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Gravity affects time because it is one of the fundamental forces that govern the universe. According to Einstein's theory of general relativity, gravity is not just a force that pulls objects towards each other, but it is also a curvature of space and time. This means that the presence of massive objects, such as planets, causes a distortion in the fabric of space-time.

Think of space-time as a rubber sheet, with planets and other massive objects creating dips and curves in it. This curvature of space-time is what we experience as gravity. And just as a marble rolling on a curved sheet will experience a change in its path, objects moving through the curved space-time will also experience a change in their trajectory.

Now, when it comes to time, this curvature of space-time also affects it. Time is not a separate entity from space, but rather a part of the fabric of space-time. So, as space is curved by the presence of massive objects, time also gets distorted. This means that time moves slower in the presence of strong gravitational fields, such as near a black hole.

This phenomenon, known as gravitational time dilation, has been confirmed through various experiments and observations. For example, atomic clocks placed at different altitudes on Earth run at slightly different rates due to the difference in gravitational pull.

In summary, gravity affects time because it is a fundamental force that causes a distortion in the fabric of space-time, which includes both space and time. This concept is crucial to our understanding of the universe and has been confirmed by numerous experiments and observations.
 

1. Why does gravity affect time?

Gravity affects time because it is a fundamental force of nature that causes objects with mass to be attracted to one another. According to Einstein's theory of general relativity, gravity is not just a force, but it also warps the fabric of space-time. This warping of space-time causes time to slow down in the presence of a strong gravitational field.

2. How does gravity affect time?

Gravity affects time by warping the fabric of space-time. This warping causes time to slow down in the presence of a strong gravitational field. The stronger the gravitational field, the greater the warping effect and the slower time moves.

3. Does gravity affect time differently in different places?

Yes, gravity affects time differently in different places. The strength of gravity is directly related to the amount of mass in an object. Therefore, the closer an object is to a massive object, the stronger the gravitational field will be and the more time will be affected. This means that time will move slower in places with a stronger gravitational field, such as near a planet or star, compared to places with a weaker gravitational field, such as in space.

4. Can gravity affect the flow of time?

Yes, gravity can affect the flow of time. In extreme cases, such as near a black hole, the warping of space-time caused by gravity can be so strong that time appears to stand still. This is known as time dilation, and it means that time is flowing at a different rate for an observer in a strong gravitational field compared to someone in a weaker gravitational field.

5. What are some consequences of gravity affecting time?

The consequences of gravity affecting time are related to the concept of time dilation. For example, astronauts orbiting the Earth experience time at a slightly slower rate than people on the surface, due to the stronger gravitational field in orbit. This means that when they return to Earth, they have effectively time-traveled into the future. Additionally, the effects of gravity on time are important in understanding the behavior of objects in the universe, such as the orbits of planets and the formation of galaxies.

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